#include"chen.h"

int main( void )
{
	pid_t pid;

	if ( ( pid = fork( ) ) < 0 ) {
		err_sys( " fork error" );
	} else if ( pid == 0 ) {
		if ( (  pid = fork( ) ) < 0 ) {
			err_sys( " fork error" );
		} else if (pid > 0)
			exit(0);

		sleep(4);
		fprintf(stderr, "second child, parent pid = %d\n", getppid());
		exit(0);
	}

	if ( waitpid( pid, NULL, 0 ) != pid )
		err_sys( "waitpid error" );


	exit( 0 );
}
